bio lecture 5

Question 1

What is pain?

Answer 1

A complex physiological and psychological experience.

Question 2

What are nociceptors?

Answer 2

Specialized sensory receptors that detect pain and signal potential harm.

Question 3

What happens when skin or organs get damaged?

Answer 3

Prostaglandins are produced, causing vasodilation and sensitizing free nerve endings.

Question 4

What are the two types of nociceptors?

Answer 4

• Highly myelinated axons (Aδ fibres)
• Unmyelinated axons (C fibres)

Question 5

What type of pain do Aδ fibres conduct?

Answer 5

Mechanical pain very quickly and precisely.

Question 6

What type of pain do C fibres conduct?

Answer 6

Mechanical, heat, and chemical pain slowly and less precisely.

Question 7

What is the role of the primary somatosensory cortex?

Answer 7

Processes pain sensation and indicates where the pain is located.

Question 8

What is phantom limb pain?

Answer 8

Pain felt in a limb that has been amputated, suggesting the brain constructs pain experiences.

Question 9

What are the two mechanisms of pain in the brain?

Answer 9

• Pain Sensation (physical) » Primary Somatosensory Cortex
• Unpleasantness perception » Anterior Cingulate Cortex

Question 10

What is hypnosis-induced analgesia?

Answer 10

A non-drug approach that can reduce pain perception.

Question 11

What does the placebo effect activate?

Answer 11

The dorsolateral prefrontal cortex, leading to pain suppression.

Question 12

What is the role of the descending analgesia circuit?

Answer 12

Reduces pain by inhibiting pain signals from entering the CNS.

Question 13

What are NSAIDs?

Answer 13

Non-Steroidal Anti-Inflammatory Drugs like aspirin and ibuprofen.

Question 14

How do NSAIDs work?

Answer 14

Inhibit Cyclo-Oxygenase enzymes (COX-1 and COX-2), reducing prostaglandin production.

Question 15

What is the mechanism of action for paracetamol?

Answer 15

Agonist to CB1 receptors and converts to AM404, affecting nociceptors.

Question 16

What are opiates?

Answer 16

Drugs derived from the opium poppy or synthetically created for pain relief.

Question 17

What are the three types of opioid receptors discovered in 1973?

Answer 17

• Delta
• Kappa
• Mu

Question 18

What are the short-term effects of opiates?

Answer 18

• Pain relief
• Cough suppression
• Diarrhoea suppression
• Sedation
• Euphoria

Question 19

What triggers the addictive potential of opiates?

Answer 19

They affect the Mesotelencephalic Dopamine System, increasing dopamine release.

Question 20

What is cannabis derived from?

Answer 20

The Cannabis plant.

Question 21

What are the active compounds in cannabis?

Answer 21

• THC (psychoactive)
• CBD (medicinal effects)

Question 22

What are some short-term effects of recreational cannabis use?

Answer 22

• Reduced anxiety
• Distorted time perception
• Heightened sensations

Question 23

What medicinal effects does cannabis have?

Answer 23

• Reduces nausea
• Increases appetite
• Decreases seizures
• Reduces pain

Question 24

What negative effects can cannabis cause?

Answer 24

• Reduced motor coordination
• Intoxication similar to alcohol

Question 25

Fill in the blank: Prostaglandins are produced in response to _______.

Answer 25

[tissue damage]

Question 26

True or False: Pain is only a physical sensation.

Answer 26

False

Question 27

What does the anterior cingulate cortex do?

Answer 27

Processes the unpleasantness perception of pain.

Question 28

What is capsaicin used for?

Answer 28

Topical relief for muscle pain. (pain-relieving substance directly to the skin over sore muscles, instead of taking pills)

Question 29

What does capsaicin trigger in nociceptors?

Answer 29

A pain response that depletes substance P from synapse.

Question 30

What is naloxone?

Answer 30

An opiate receptor blocker that inhibits the effects of opiates.

Question 31

How does acupuncture work?

Answer 31

Triggers activation of the descending analgesia circuit.

Question 32

What are some therapeutic effects of cannabis?

Answer 32

Cannabis can reduce pain, ease glaucoma symptoms, and dilate bronchioles. ## Footnote It is also noted to be as effective as opiates for pain relief.

Question 33

What are the negative effects of cannabis use?

Answer 33

Negative effects include reduced motor coordination, slower reflexes, memory and attention impairments, paranoia, and panic attacks. ## Footnote Intoxication effects can be similar to alcohol.

Question 34

What is the origin and function of endogenous ligands?

Answer 34

Endogenous ligands are produced naturally within the body and bind to specific receptors to regulate physiological processes. basically anything that binds to a receptor ## Footnote Examples include neurotransmitters like dopamine and hormones like insulin.

Question 35

What distinguishes exogenous ligands from endogenous ligands?

Answer 35

Exogenous ligands are introduced from outside the body and can mimic, block, or alter the function of endogenous ligands. ## Footnote Examples include drugs like morphine and toxins like nicotine.

Question 36

What roles do THC and CBD play in cannabis?

Answer 36

THC acts as a partial CB1 and CB2 receptor agonist, while CBD serves as a CB1 antagonist that modulates THC effects. ## Footnote The ratio of THC to CBD can influence the experience of the user.

Question 37

Where are cannabinoid receptors primarily located?

Answer 37

CB1 receptors are mainly in the brain, and CB2 receptors are found in the immune system. ## Footnote Cannabinoid receptors are also present in areas like the spinal cord and hypothalamus.

Question 38

What are endocannabinoids and how do they function?

Answer 38

Endocannabinoids are neurotransmitters released from the postsynaptic cell that bind to receptors on the presynaptic cell, unlike traditional neurotransmitters. ## Footnote This process occurs particularly at GABA-ergic synapses in the hippocampus.

Question 39

What is 'depolarization induced suppression of inhibition'?

Answer 39

It is a phenomenon in the hippocampus where endogenous cannabinoids released from postsynaptic neurons inhibit GABA release from presynaptic neurons. ## Footnote This leads to increased neuronal depolarization and action potentials.

Question 40

How does cannabis affect memory?

Answer 40

Cannabis use disrupts the natural patterns of neuronal activation, leading to memory problems and loss of memory formation. ## Footnote This is due to cannabinoids stopping the release of neurotransmitters at synapses.

Question 41

What are the long-term effects of cannabis use?

Answer 41

Long-term effects can include memory and attention impairment, slower decision-making, increased risk of psychosis, and IQ decline with early persistent use. ## Footnote High-potency strains like 'skunk' are particularly associated with psychosis.

Question 42

What is the legal classification of cannabis and opiates?

Answer 42

Opiates are classified as Class A drugs, while cannabis is classified as Class B. ## Footnote This indicates that opiates carry higher legal consequences than cannabis.

Question 43

How does THC affect psychological dependence?

Answer 43

THC increases dopamine release in the Nucleus Accumbens, contributing to psychological dependence. ## Footnote Physical dependence on cannabis is considered low.

Question 44

Fill in the blank: The two most common endogenous ligands for cannabinoid receptors are _______ and 2-AG.

Answer 44

Anandamide

Question 45

True or False: Cannabis can cause overdose.

Answer 45

False

Question 46

What is a unique case study involving an individual with a defect in the FAAH enzyme?

Answer 46

A 66-year-old woman required no post-surgical analgesia due to very high blood levels of anandamide, leading to a lack of pain sensation. ## Footnote This case highlights the potential of targeting FAAH for pain treatment.